Dc Motor Drive Basic Questions

[calstar]

Very basic questions here. Picked up what a appears to be a good quality made in USA DC motor from a treadmill and want to use it on a lathe, here are the specs:



I want to use a MINARIK model MM23001C. adjustable SCR speed controller on the motor, here are its specs:



First question, the controller specs show Armature voltage (115 VAC IN): 0-90 VDC and Armature voltage (230 VAC IN): 0-180 VDC . My motor shows 120VDC but I'm nearly positive it was used on 115AC to run the treadmill(and not 230, is this right?). Will the motor only run on 230VAC?

Second question, is the motor rating of 2.75hp to much for the controller (as it's specs show only up to 2hp)?

I've tested the motor using a 12v drill battery and it runs fine, if this controller will not work what are other options available that will? I want to use use a DPDT off center switch as well as a main off switch and a potentiometer.

Another option is to use the original controller which seems to be in good condition(I removed it with the motor from the treadmill at the scrap yard) but don't know how to test it. Could I run 115ac to the controller(AC input in upper left corner of pic) with the motor connected to it or is that a bad idea(don't want magic smoke escaping)? It seems like the Minarik will be an easier install, I can at least make sense of the installation diagram, but maybe using the original won't be so difficult once I have a better understanding of it. Here's a pic of the controller, the AC in is in the upper left corner.



thanks in advance for any help,

Brian

 

[British Steel]

The problem is going to be that the Minarik controller is only rated for 10 Amps, the motor pulls 20 at full load...

The original controller should be rated for full load, but it's hard to see how its external controls should connect - there seem to be several small multi-way connectors on the board, you may need to look at what was originally plugged in where, and work from that?

Do you have the rest of the treadmill's electrics, and can you post a (higher-resolution) close-up of the controller PCB so folks can maybe read the labelling on the connectors?

Dave H. (the other one)

 

[Kernbigo]

use the thread mill controller and it will work ok, to many amp for the Minarik

 

[John Hasler]

It'll work on 120VAC.

You could set the torque control on the Minarik to limit the current to 10 amp but that would be sad: you'd be giving up half the capability of that lovely motor. Get us more pictures of the controller. How many wires come off the motor? Did you get all of th electronics and cabling?

 

[calstar]

The controls for the treadmill(parts that the walker/runner uses) weren't with it, I got everything that was there. I'll take pics of the control board tomorrow and p0st them here. It would be nice to have the full load 20amp capability but even limiting it to 10amps would probably still be better(more torque?) than the 2hp 220AC motor that was on it. Here is a link to the set up I'm looking to have or something similar, I have the same lathe.
http://rvbprecision.com/garage-entertainment/metal-lathe-dc-motor-conversion-jet-12-x-36-bd.html I believe this fellow is a member here but don't recall his forum name. He states his 3/4 hp 90VDC motor is plenty strong for the work he does, so as I said above I could live with the 10amps route.

thanks, Brian

 

[xman_charl]

Have used those controllers from surplus center. Work okay.
Controller has jumpers, 90 vdc, or 120 vdc.

3/4 would be okay, that treadmill motor would be overkill.


my 2 cents


Charl

 

[calstar]

Thanks Charl, thats what I was thinking after reading RVBprecision's mod page. I contacted one of the vendors for the Minarik, Galco, they had a controller that would give me 15amps but it was $380, too spendy for me. Here are the pics I took of the controller, might need a few more to cover it all, also includes diagram that was on the motor cover. The upper PCA was not there, it was cut at the serial interconnect cable but I do have all the wiring and pic of what went where. I'm not against using the controller if its possible, but couldn't do it without some step by step help, thats why I'm leaning toward the Minarik.

This is probably way over simplified but.......couldn't I put a simple on/off switch on the line cord and a dpdt switch in the red/ black, for foward/reverse, to the motor from J6 in the diagram and also a potentiometer after the dpdt on the same black/red to the motor? Just throwing it out there, not concerned showing my lack of knowledge!

thanks, Brian

 

[John Hasler]

J5 (which I can't find in the photos) is the key. The controller gets commands via a serial digital link to the micro in the front panel.

 

[calstar]

Thanks John, J5 is right above R11 on the right side in the pic below, I stuck the cut end of the serial connecter in it so the J5 is hidden, but its the "grey box" right above R11.



I can take a pic of it tomorrow along with some info printed on the cable.

So where do I go from here?

Brian

 

[calstar]

Here are the pics of the pin connector, J5, and the cable.

Brian